In interior parts such as decorative articles such as parcel trays for use in vehicles such as automobiles and airplanes or decorative laminates used for indoor walls, a resin hollow molded article having arranged therein a reinforcing material such as a material, steel tube and flame, having an air layer such as an adiabatic material or acoustic material as an intermediate member of an interior part by sheet blow molding is described in Japanese Patent Application Laid-Open (JP-A) No. 10-80982. In addition, a resin hollow molded article formed by blow-molding a sheet-like parison as well as inner-packaging a foam during blow molding is described in JP-A-2000-218682.    Patent Document 1: JP-A-10-80982    Patent Document 2: JP-A-2000-218682